Why Biodiversity Is Important: Sustaining Ecosystems with Ecological Diversity and Genetic Diversity

February 1, 2010 Gaia Discovery

Davao City, 1 February 2010. “If any part of the web suffers or breaks down, the future of life on the planet will be at risk.” Those words were spoken by Klaus Töpfer when he was still the executive director of the United Nations Environment Program. His observation led the UN General Assembly to proclaim 2010 as the International Year of Biodiversity.

“Biodiversity, the variety of life on Earth, is essential to sustaining the living networks and systems that provide us all with health, wealth, food, fuel and the vital services our lives depend on,” the Secretariat of the Convention on Biological Diversity said in a statement.

Biodiversity – coined from biological diversity – is most often thought of as the variety of organisms on earth. Yet it also includes two other factors: ecological diversity (the variety of ecosystems and ecological communities) and genetic diversity (the range of genetic differences found within and between species).

“All three aspects are crucial for the success and development of life on earth,” explains People and the Planet, a group raising environmental concerns based in London. “Since environmental conditions at every level are constantly changing, only diversity can ensure that some individuals and species will be able to adapt to the changes.”

Species declines and extinctions have always been a natural part of that process, but there is something disturbingly different about the current extinction patterns. “Like the dinosaurs 65 million years ago, humanity now finds itself in the midst of a mass extinction: a global evolutionary convulsion with few parallels in the entire history of life,” wrote John Tuxill and Chris Bright, authors of Losing Strand in the Web of Life. “But unlike the dinosaurs, we are not simply the contemporaries of a mass extinction – we are the reason of it.”

Tarsiers are dwindling in numbers.

Rodrigo Fuentes, executive director of the Asean Center for Biodiversity, said deforestation, large-scale mining, massive wildlife hunting and other “irresponsible human activities have increased extinction levels dramatically over the past decades at 100 to 1,000 times the normal rate.”

Why so much ado about biodiversity loss? “The loss of species touches everyone, for no matter where or how we live, biodiversity is the basis for our existence,” pointed out Tuxill and Bright. In other words, without biodiversity man ceases to exist.

Dr. Raven cites three reasons why biodiversity should be conserved and protected; these are ethical and aesthetic, economic, and services. To explain the first reason, he quotes the words of Paul Ehrlich and Ed Wilson, authors of Extinction: The Causes and Consequences of the Disappearance of Species: “Because Homo sapiens (human beings) is the dominant species on Earth, we and many others think that people have an absolute moral responsibility to protect what are our only known living companions in the universe.”

The Holy Bible itself states so. God told Adam and Eve, the first human beings: “Rule over the fish of the sea and the birds of the air and over every living creature that moves on the ground” (Genesis 1:28).

In terms of economic value, Dr. Raven says the world’s population use organisms for food, medicines, chemicals, fiber, clothing, structural materials, and energy, among many others. “Biodiversity provides a wealth of genes essential for maintaining the vigor of our crop and livestock,” Tuxill and Bright reminded.

For instance, Asian cattle have been crossed with dairy breeds of Europe to boost their milk and meat output. On the other hand, a high-yielding variety of rice developed at the Laguna-based International Rice Research Institute is a cross between a Chinese dwarf strain and a tall, traditional plant from Indonesia.

Some 100 kinds of plants – including rice, wheat, corn, potato, and cassava – provide the great majority of the world’s food. “There might be tens of thousands of other plants that have edible parts and might be used more extensively for food, and perhaps brought into cultivation, if we knew them better,” Raven notes.

That was what God told Adam and Eve, too: “I give you every seed-bearing plant on the face of the whole earth and every tree that has fruit with seed in it. They will be yours for food. And to all the bests of the earth and all the birds of the air and all the creatures that move on the ground – everything that has the breath of life in it – I give every green plant for food” (Genesis 1:29-30).

More than 60 percent of the world’s people depend directly on plants for medicine. The Chinese, for instance, use more than 5,000 of the estimated 30,000 species of plants found in the country for medicinal purposes. In the United States, some 25 percent of drugs prescribed include chemical compounds derived from wild organisms.

Two of the most important anti-cancer drugs in the world come from the rosy periwinkle, found in Asia’s tropical rainforests. Taxol, the only drug that shows promise against breast cancer and ovarian cancer, was initially found in the western yew. The puffer fish provides toxin used in nervous system research.

Biodiversity provides pollination services, mostly in the form of insects, without which the world could not be fed. Frogs, fish, and birds provide natural pest control; mussels and other aquatic organisms cleanse the water supplies; plants and microorganisms create the soils.

By saving the world’s biodiversity, man also saves the natural ecosystems in which they thrive and dwell. Ecosystems, functioning properly, are responsible for the Earth’s ability to capture energy from the sun and transform into chemical bonds to provide the energy necessary for the life processes of all species, including human beings.

“Clearly, much of the quality of ecosystem services will be lost if the present episode of extinction is allowed to run unbridled for much longer,” Dr. Raven contends.

“Protection of biodiversity should be one of the top priorities of any meaningful strategy to safeguard the world’s biological heritage,” suggests John C. Ryan, author of Life Support: Conserving Biological Diversity.

The Philippines, with more than seven thousand islands, is considered by respected scientists as one of the countries with the highest degree of biodiversity in the world, second only to Brazil. Its estimated two million species include 8,000 flowering plants (including the endangered waling-waling), 395 birds (Philippine eagle is one of them), 180 mammals (tarsier and tamaraw are examples), and 293 reptiles and amphibians (Philippine crocodile, hawksbill turtle, and reticulated python, to name a few).

Unfortunately, the Philippines is listed as one of the world’s five “hottest of the hot spots,” a hot spot being an area whose high biodiversity is gravely threatened. “A few decades ago, the wildlife of the Philippines was notable for its abundance; now, it is notable for its variety; if present trend of destruction continues, Philippine wildlife will be notable for its absence.” Observed Dr. Lee Talbot, who used to head the Southeast Asia Project on Wildlife Conservation for Nature and Natural Resources.

Meanwhile, mass extinction continues. “The planet would be biologically depleted for millions of years, with consequences extending not only beyond the lives of our children’s children, but beyond the likely lifespan of the entire human species,” says Dr. James Kirchner, an American professor of earth and planetary science at University of California.

But there is still a glimmer of hope. As Tuxill and Bright put it: “Humans, after all, are not dinosaurs. We can change. Even in the midst of the mass extinction, we still largely control our destiny, but only if we act now. The fate of untold numbers of species depends on it. And so does the fate of our children, in ways we can barely begin to conceive.”